Steve Smith, Mitchell Starc ruled out of Australia's white-ball series against Proteas

Smith is nursing a tendon injury to his left wrist which will keep him sidelined for up to another four weeks and will miss both the three-match T20 series and five ODIs in South Africa, that starts on 30 August.

Fast bowler Starc was initially only selected for the ODI leg of the tour but has been withdrawn after experiencing soreness in his groin following a gruelling Ashes series in England.

Australia chief selector George Bailey said both players' fitness is a priority ahead of World Cup in India that begins in October.

"The compacted Ashes series and the World Test Championship was a heavy load for the group, and we are taking a conservative approach to the build-up to the World Cup," Bailey said.

"With the World Cup the priority of the squad, it was determined on advice that it was best for Steve and Mitchell to join the group in India by which time we expect them to be fully fit and available for the Indian ODI series, plus the World Cup warm-up fixture."

With Pat Cummins having already confirmed he will be sidelined for the South Africa tour as he recovers from a fractured wrist, Mitchell Marsh will take on the ODI captaincy to go with the leadership of the T20 side for the matches against the Proteas.

Smith's absence has offered an ODI reprieve for Marnus Labuschagne, who now joins the squad for the 50-over games against the country of his birth.

Labuschagne was left out of Australia's extended 18-player World Cup squad, with Bailey indicating a lack of consistency had cost him his spot.

Australia white-ball tour to South Africa:

August 30: First T20I, Durban

September 1: Second T20I, Durban

September 3: Third T20I, Durban

ODI series:

September 7: First ODI, Bloemfontein

September 9: Second ODI, Bloemfontein

September 12: Third ODI, Potchefstroom

September 15: Fourth ODI, Centurion

September 17: Fifth ODI, Johannesburg

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